Restoration (Inspection) of the Horizontal Stabilizer Trim Actuator (HSTA)
Effectivity: Challenger 300/350 aircraft
ATA: 27
By: Patrick Bernèche - Flight Controls Specialist This article is to inform operators of Challenger 300/350 aircraft of the introduction of a new Time Limits/Maintenance Checks (TLMC) Task 27-40-00-108** for the Restoration (Inspection) of the Horizontal Stabilizer Trim Actuator (HSTA). This task is applicable to HSTA Part No C47100-003/004/005 and the interval is 120 months (component).
Operators should be aware of the Phase-in information provided by the new TLMC
task 27-40-00-108** to make sure the restoration (inspection) is done within the recommended compliance time.
The restoration task must be done at the vendor facility and HSTA removal is required. Ground Support Equipment (GSE) is needed for HSTA replacement and when planning these tasks, we recommend contacting Bombardier in advance to confirm availability of the required GSE.
Two options are proposed to support the restoration program. Exchange HSTA are available, or the restoration can be managed through Bombardier customer repair and overhaul (CR&O). HSTA rental option is also available if required.
Parts are limited, so in order to ensure that HSTAs can be provided on time, advanced scheduling is required. HSTA inventory is managed via a dedicated schedule by the In-Service Implementation team (ISIT). To ensure effective planning, ISIT must be contacted in advance at bacs_isit@aero.bombardier.com.
The HSTA serial number, hours, cycles and the date of manufacturing will be requested during the scheduling process. The date of manufacturing can be found on maintenance records or with a visual check of the HSTA identification plate.
Moog, the HSTA vendor released the service information letter (SIL) C47100-SIL-01 that can be used as reference for planning purposes. The SIL is available on the Bombardier customer portal / Library. Moog SIL C47100-SIL-01 provides HSTAs original delivery dates which is usually within one (1) month after the manufacturing date. It also provides the dates that each HSTA was returned in inventory after upgrade from Part No C47100-003 to Part No C47100-004 or Part No C47100-005.
Please note that when this upgrade is done, credit can be taken for the restoration (inspection) TLMC task 27-40-00-108** and the “upgrade date” provided by Moog SIL can be used to calculate the number of years before the next restoration.
If you have any questions concerning this new TLMC task, please contact your local Field Service Representative or the Customer Response Center (CRC).